Leading members of the Congressional Black Caucus sharply criticized Sen. Bernie Sanders on Thursday for being “missing in action” on issues close to the African-American community.

During an endorsement event for Hillary Clinton, African-American lawmakers said that Sanders, a democratic socialist from Vermont, does not have a history of activism for minorities that could rival Clinton's.

Story Continued Below

Georgia Rep. John Lewis, the last living member of the “Big Six” civil rights activists, said he never met Sanders during the tumultuous 1960s in the South.

“To be very frank, I never saw him, I never met him,” said Lewis. “I chaired the Student Nonviolent Coordinating Committee for three years, from 1963 to 1966. I was involved in sit-ins, in the Freedom Rides, the March on Washington, the March from Selma to Montgomery ... but I met Hillary Clinton.”

Sanders marched in Washington during the civil rights movement and was also involved in the Student Nonviolent Coordinating Committee. As a college student, Sanders joined the March on Washington in 1963. But the CBC members said that experience doesn’t compare to Clinton’s background in the South.

“There is no comparison. Hillary Clinton has been there from the beginning. Bernie Sanders has not just been missing in action, he’s been on the wrong side,” said Rep. Hakeem Jeffries, a New York Democrat, referring to gun control legislation.

Jeffries, a sophomore Democrat, has been a vocal supporter of Clinton’s — and he's often been tapped to bolster her candidacy among African-Americans.

Winning the support of senior black lawmakers is a major get for Clinton as she struggles to maintain her front-runner status in the Democratic primary. She narrowly eked out a win in Iowa but got trounced in New Hampshire, losing by double digits to Sanders. Now, Clinton’s team is looking to South Carolina and Nevada, and strong backing from minority voters in those states, to buoy her campaign going into March.

Clinton has been quick to tackle issues close to the CBC since launching her campaign last winter. She gave an early policy address on criminal justice reform and has traveled to meet with the families of victims of police shootings.

On Thursday, Clinton criticized Cleveland officials who are looking to make Tamir Rice’s family pay for his ambulance ride after he was shot by a police officer in 2014.

“Asking Tamir's family to pay for his ambulance is heartless. Cleveland should drop this fee,” Clinton said on Twitter.

Clinton isn't the only one courting minority voters.

Ahead of South Carolina, Sanders has been burnishing his credentials among African-Americans. So far, the Vermont senator has mostly relied on white voters to spur his candidacy forward, but as the primary battle continues into the South he'll need to diversify his base. Sanders was helped this week by an endorsement from Harry Belafonte — a noted African-American activist. Sanders also met with the Rev. Al Sharpton at a Harlem restaurant.

The endorsement from senior black lawmakers could help build a firewall for the former secretary of state. She’ll need to excite African-American voters in South Carolina to secure a victory when Democrats from the first Southern state vote on Feb. 27.

Rep. Cedric Richmond, a Louisiana Democrat, said while the CBC is encouraged by Sanders’ ability to turn out new Democratic voters, he hopes younger voters — who are flocking to Sanders — will take a more thorough look at Clinton’s platform. Richmond said her policies are more realistic than Sanders' campaign promises.

He urged young voters to support the candidate who can “make the revolution” happen.

New York Democrat Rep. Gregory Meeks, chairman of the CBC's political action committee, said that now that there is an official endorsement for Clinton, African-American lawmakers would ramp up their campaigning for her. He noted that the PAC plans to max out giving to her campaign as well.

Nearly a half-dozen black lawmakers are expected to spend time in South Carolina campaigning for Clinton ahead of the first-in-the-South Democratic primary there. Ohio Rep. Marcia Fudge said some members of the delegation will spend nearly a week in the state, visiting churches and attending rallies for Clinton. Also traveling to South Carolina are Lewis and Reps. G.K. Butterfield, chairman of the black caucus, and Emanuel Cleaver, a Missouri Democrat who has been a longtime supporter of Clinton's.